Welcome to my blog. HIV prevalence is not a reliable indicator of sexual behavior because the virus is also transmitted through unsafe healthcare, unsafe cosmetic practices and various traditional practices. This is why many HIV interventions, most of which concentrate entirely on sexual behavior, have been so unsuccessful.

Even in South Africa HIV prevalence among white people is very low. But national prevalence is amongst the highest in the world and there are more HIV positive people in South Africa than in any other country. While America has the worst HIV epidemic in the developed world, with over 1.1 million HIV positive people, the majority of infections arise among men who have sex with men and (to a lesser extent) intravenous drug users. HIV infection among white heterosexuals who have no serious risks, such as receptive anal sex or intravenous drug use, is very low.

The American who tweeted the first stupid, but sadly true, remark offended so many people that she arrived in South Africa to find that a storm had erupted on Twitter and she had lost her job. So, to make matters worse, she made a statement to a South African newspaper which contained a dangerous but often heard falsehood:

"For being insensitive to this crisis -- which does not discriminate by race, gender or sexual orientation, but which terrifies us all uniformly -- and to the millions of people living with the virus, I am ashamed."

HIV most definitely does discriminate by race, gender and sexual orientation. This is not a new discovery, either. It may be an acceptable thing to say in certain circles, but we should never forget the differences between HIV in Africa, where the majority of HIV positive people live, and HIV in developed countries, where HIV is less prevalent overall, and is rare among heterosexuals who have no serious risk behaviors.

Justine Sacco, who tweeted the remark, is so right to think that she is very unlikely to be infected with HIV; a lot less likely than a black African, and also less likely than a black or Latino/Latina American. It is disturbing to think that so many people continue to believe or say otherwise. Why is HIV prevalence so high among black Africans and black/African Americans, yet comparatively low among white people, especially white men who engage in no serious risk behaviors?